Modeling of CO2 Adsorption on Activated Carbon and 13X Zeolite via Vacuum Swing Adsorption

29th Symposium of Malaysian Chemical Engineers 2016

Zarghampoor, M.H.^1 ; Mozaffarian, M.^1 ; Soleimani, M.^1 ; Takht Ravanchi, M.^2

Department of Chemical Engineering, Amirkabir University of Technology, No. 424, Hafez Ave., Tehran, Iran^1

Catalyst Research Group, Petrochemical Research and Technology Company, National Petrochemical Company, Tehran, Iran^2

关键词: Average absolute deviation;    Breakthrough time;    Equilibrium adsorption;    Equilibrium adsorption capacity;    Mass transfer rate;    Monolayer adsorption;    Second-order models;    Vacuum swing adsorptions;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/206/1/012004/pdf
DOI  :  10.1088/1757-899X/206/1/012004

来源: IOP

【 摘 要 】

Due to carbon dioxide role in global warming, low CO2emission limits have been established in recent years. This has led to a variety of studies on CO2removal approaches. In this study, a VSA cycle consisting of two packed beds is considered for CO2removal from flue gas. An atmospheric stream containing 20 CO2and 80 N2is fed to the beds at 50°C. Two adsorbents, namely Zeolite 13X and activated carbon were selected to compare their performance. Due to the monolayer adsorption of CO2and N2on these adsorbents, the Toth isotherm was used for equilibrium adsorption estimation. A quasi-second order model was considered for the mass transfer rate prediction due to low CO2concentration. The modeling results showed that the average absolute deviation for equilibrium adsorption capacity prediction was 2, and the CO2breakthrough time curve was predicted with less than 2.5 deviation. Based on the results, the VSA cycle time for zeolite 13X bed will be 3.5 times of the activated carbon bed. Another advantage of Zeolite 13X is that in each process cycle, 80 of adsorbent will be used, while only 74 of activated carbon in beds is used. The advantage of activated carbon bed is its better regeneration capability, since the activated carbon will be regenerated 5 more than zeolite 13X at a vacuum pressure of 0.02bar.